Lifting jack



Patented May 11i, 1926.

UNITED STATES PATENT OFFICE.

NORMAN W. LITTLEJOHN, or NnosHoQMIssoUnr, Assrenon or cnn-HALF To SAMUEL A. KENOYER, or ivriAivrr, OKLAHOMA.

LIFTING JACK.

Application filed May 28, 1925.

This invention relates to lifting acks and more. particularly to a single throw lack especially adapted for use on light weight automobiles.

An important object of the invention is to provide va device of the above mentioned character wher-ein a. single downward move` ment of the operating handle isv adapted to lift the jack to its full height.

A further object is to provide automatic means for latching the lift. bar in raised position and automatically releasing it when the jack is to be lowered.

Other objects and advantages of the invention will be apparent during the course of the following description.

In the drawings I have shown one embodiment of the invention. In this showing:

Figure 1 is a side elevation of the jack in lowered position, parts being shown in section,

Figure 2 is a similar view showing the parts in raised position,

Figure 3 is a section taken fsubstai'ltially on line 3-3 of Figure 1.7

Figure l is a similar view on line 4 4; of Figure 1, and,

Figure 5 is a detail perspective of the latching mechanism.

Referring to the drawings the numeral designates a standard or support as a whole including side walls 11 and a rear wall 12. A lift bar 13 which is substantially rectan gular in cross .sect-ion, and preferably hollow, is arranged to slide vertically within the standard in contact with the side and rear walls thereof as shown in Figure t. The standard is provided with a substantially conventional .engaging head lll adapted to engage an axle of a vehicle as will be under stood. An engaging member 15 is also provided for use on auto-mobiles equipped with balloon tires. As shown the engagin member 15 is provided with an upwarc ly eX- tending portion 16 having a laterally projecting upper end 17 which in turn is provided at it-s forward end with a depending lug 18. The upper portion of the end wall 12 of the standard is cut away as at 19 to permit a portion of the inner face of the upstanding end 16 to firmly contact with the lift bar, as shown in Figure 1. The lift bar is provided bene-ath thehead l14 with an opening 20 through which the upper end 17 of the engaging member 15 extends, and

Serial No. 33,523.

the lift bar is provided with an inwardly extending lip 21 which is spaced from the opposite wall of the lift bar to permit the reception of the depending lug 18 to prevent outward movement of the upper end "of the .engaging member 15.

The side walls 11 extend rearwardly as at 22 Iand `an operating lever is arranged between these extended portions of the side walls.l As shown7 the lever 23 is provided with an ear 3 in which is journalled a pivot pin 24 which extends through the eX- tendcd portions 22 of the side walls of the standard. lThe lever 23 is provided with a socket 25 adapted to receive a relatively long operating handle 2G. The inner end Off the lever 23 is bifurca-ted to provide arms 27 between which is arranged a link 28. The link 28 is vprovided intermediate its ends with ay longitudinal slo-t 28 to receive a pin 29 carried by the bifurcated arms 27. One end of the link 28 is pivotally connecte-d 'to the side walls of the standard by a pin y30. The opposite end of the link 28 is provided with a pivot pin 31 which is pivotally received in openings formed in a pair of links 32 arranged on opposite sides of the link 28. as shown in Figure 4. The opposite ends of the links 32 extend through openings 33 formed in the forward wall of the lift bar, as shown in Figure 3, and are pivotally connected by a Apin 34 with the side walls of the lift bar.

A pivoted latch is arranged adjacent one side wall of the standard as shown in Figures 3 and ft. A boss 33 is preferably formed integral with 'the side wall of the standard and is provided with a pivot pin 37 which is received in the lower end of t-he latch 35. The .latch is provide-d adjacent its upper end with a horizontal shoulder 38 and is also provided adjacent one edge with a laterally projecting lug 39 for a purpose to be described. The latch 35 is furtherprovided intermediate its ends with a substantially arcuate cut out portion 4L() which is adapted to be arranged opposite the arcuate face l1 of the operating lever when the device is in raised position, as shown in liigure 2. The outer face of the arm 27 ofthe operating lever adjacent the latch 35 is provided with an arcuate extension l2 which extends loutwardly in alinement with the latch as shown in Figure Ll.

As shown in Figures 1 and 2 the lift as will be obvious.

bar is provided near the lower end of its inner wall with a substantially horizontal shoulder 43 which is adapted to rest on the shoulder 38 when the lift bar is in raised position, as shown in Figure 2. When the device is in raised position, it will be noted that the lug 39 of the latch is arranged adjacent one edge of one of the links 32 as shown in dotted lines in Figure 2.

Means are provided for maintaining the latch 35 in locked or unlocked position. As shown in detail in Figure 5, a substantially vertical bar 44 is pivotally connected at its upper end as at 45 with the upper end of the latch 39. A spring 46 is connected at its upper end to the lower end of the bar 44 and at its lower end to the base of the standard within the walls thereof. It will be obvious that the center of the pin 45 will be arranged slightly tothe left of the center ofthe pin 37 when the latch 35 is in the solid line positions shown in Figures 1 and 2, and will be arranged .slightly to the right of the center of the pm 37 when in the dotted line position shown in Figure 2.

The operation of the device is as follows:

The jack is placed in position beneath the axle of a vehicle with the lift bar in lowered position, either of the engaging members 14 or 15 being employed according to the type of tire equipment. The outer end of the handle 26 is then depressed by the hand or foot of the operator to swing the lever 23 about its pivot 24. This action moves the pin 29 upwardly and inwardly thus swinging the link 28 about its pivot 30. The lower end of the link 28, through its pivot pin 31, then` moves the forwaro` end of the links 32 inwardly and upwardly, thus raising the lift bar through the pin 34, During this action it will be apparent that` the tension of the spring 46 is exerted on the upper end or the latch 35 to the left of the pivot 37 as shown kin Figure 1, thus retaining the upper end of the latch in sliding engagement with the upper end of the lift bar. When the handle 26 has been fully depressed, the shoulder 43 of the lift bar will be raised a slight distance above the shoulder 38 of the latch and the spring 46 will then cause the upper end of the latch to swing to the position shown in solid lines in Figure 2, whereby the shoulder 38 will support the lift bar. With the device' in this position, it will be obvious that the lug 39 of the latch will be arranged against the forward edge of one of the links 32. When it is desired to lower the lift bar, the handle 26 is lowered slightly which again tends further to raise the lift bar a slight distance and will tend to straighten the links 28 and 32 with respect to each other. One of the links 32 as previously stated, is in contact with the lug 39,l and,t *the swinging action of the links just described will cause the latch 35 to be swung rearwardly whereby the center of the pin 45 will pass to the opposite side of the center of the pivot 37. The spring 46 will then exert a tension to maintain the cut out portion 40 of the latch in engagement with the curved face 41 of the lever 23. rlhus the shoulder 38 will be released from the shoulder 43 and the handle 26 is permitted to rise, thus lowering the lift bar. After the shoulder 43 has passed downwardly beyond the shoulder 38, the upper portion of the curved face 41 will act as a. cam to move the upper end of the latch forwardly toward the klift bar until the center of the pin 45 again swings across the pivot 37 whereby the latch will again slidably engage the rear wall of the lift bar, but will not interfere with the lowering action thereof. Thus it will be apparent that the latch 35 is adapted to automatically engage the lift bar to hold the latter in its upper or raised position, and that the curved face or cam 41 is adapted to automatically cause the latch to assume its normal position after the lowering action has been started whereby the elements of the device will be again placed in position to start the lifting action. When it is desired to use the engaging member or head 14, the engaging member 15 may be raised slightly so that the lug 18 will clear the lip 21 so that the engaging member 15 may be withdrawn laterally as will be obvious.

It is to be understood that the form of my invention herewith shown and described is to be taken as a preferred example of the same and that various changes in the shape, size and arrangement of parts may be made without departing from the spirit of the invention or the scope of the subjoined claims.

I claim:

1. A lifting jack comprising a standard, a lift bar slidably mounted in said standard, operating members for raising said lift bar, a latch normally arranged adjacent said liftbar and tending to move to operative position to hold said lift bar in raised position, said latch' being movable away from said lift bar to inoperative position, said latch being controlled by said operating members for moving it from operative position to inoperative position, and means forming a part of said operating members for returning said latch to normal position.

2. A device constructed in accordance with claim 1 wherein said last named means comprises a cam adapted to contact with said latch after said lift bar has moved downwardly a substantial distance from its raised position.

3. A lifting jack comprising a standard, a lift bar slidably mounted in said standard and provided near its lower end with a shoulder, operating members for raising said lift bar, a latch having a portion normally slidable against said lift bar and having a shoulder adapted to engage the shoulder of said lift bar when the latter is in raised position, said latch being adapted to move away from said lift bar to inoperative position, said operating members having a portion adapted to contact with said latch to move it from operative position to inoperative position, and means forming a part of said operating members for returning said latch to normal position after the shoulder of said litt bar has moved downwardly below the shoulder of said latch.

et. A device constructed in accordance with claim 3 wherein said operating members include an operating lever, said last named means comprising a cam carried by said lever.

5. A lifting jack comprising a standard,

a litt bar slidably mounted in said standardl and provided near its lower end with a shoulder, an operating lever, links connected between said lever and said lift bar, a latch pivoted at its lower end to said standard and provided adjacent its upper end with a shoulder adapted in operative position to engage beneath the shoulder oi said lift bar to maintain the latter in normal raised position, the upper end of said latch normally slidably engaging said lift bar and being movable away from said lift bar to assume an inoperative position, one of said links being adapted to engage said latch to move it to inoperative position when said lift bar is raised above its normal raised position, and a cam carried by said operating lever and adapted to move said latch to normal position when the shoulder of said lift bar has moved downwardly below' the shoulder of said latch.

6. A device constructed in accordance with claim 5 provided with resilient `means urging said latch toward or away from said lift bar.

7. A device constructed in accordance with claim 5 provided with a tension spring con*- nected at its lower end to said standard below said latch and at its upper end to the upper end of' said latch, the connection between the upper end of said spring and said latch being adapted to move to one side of the pivot of the latch when the latter is in operative or normal positions, and to the opposite side when said latch is in inoperative position.

In testimony whereof I atlix my signature.

NORMAN W. LITTLEJOHN. 

